Currently, a number of different technologies seek to provide the benefits of the Internet, and the World Wide Web in particular, to users any time and anywhere they desire it through wireless technologies. However, both the wireless devices used to access the Internet and the networks which carry information to those devices have a number of limitations.
Wireless devices are significantly smaller and less powerful than desktop or laptop devices which provide more conventional access to the World Wide Web via a web browser. The wireless networks which connect these devices to the Internet do not have the same bandwidth as land-based “wire line” systems, and provide this limited bandwidth at a higher cost, more limited availability and lower quality of service when compared with land-based systems.
One attempt to address the bandwidth limitations mentioned above utilized by the Palm VII® wireless personal assistant is known as “clipping.” In the Palm® system, a customized wireless application is written and deployed in two parts: a Web-based back-end, which serves dynamic content, and a Palm query application (PQA), which resides on the Palm VII® itself. The disadvantage of the Palm system is that its proprietary nature requires that only certain types of pages be available to the Palm device. In effect, the PQA takes a “clipping” from the website with which it is permanently associated. This means that for each site, the content distributor must write and distribute a PQA that contains all the menus and forms needed to input and output data on that site. This requires hosting extra files to build the clippings on the fly using any number of standard blank applications such as cold fusion, active server pages, or CGI. The advantage of clipping is that it keeps costly wireless transactions to a minimum. Only the information that needs to be updated is sent over the radio network. The downside is that all interactions with the website must be planned ahead of time and introduction of new material requires writing and compiling a new version of the PQA. Nor can users freely browse a large site on their own to find what they need.
One wireless application solution which is gaining popularity is wireless application protocol (WAP). WAP is a standard for bringing together wireless telephones and Internet content services regardless of the wireless network architecture or device type. WAP is designed to work with any type of underlying wireless network architecture, thereby freeing the provider to concentrate on the wireless application itself. As shown in FIG. 1, the WAP model presupposes a user agent 10, such as a cellular telephone or personal digital assistant (PDA), which is equipped with a micro browser. The WAP client 10 communicates directly with a server on the Internet 25 via a WAP gateway 20 as shown in FIG. 1. The WAP gateway server sits between a wireless carrier's network 15 on one side and the public Internet 25 on the other. (This configuration need not be limited to the public Internet, but may include private Intranets, so that gateways can be located within the carrier or corporate firewalls or both.) The WAP gateway 20 handles the interface between the two sets of network protocols, wireless WAP and wireline TCP/IP. The WAP gateway decodes and decompresses wireless terminal requests and sends it on to the appropriate web server as an ordinary HTTP request.
Certain wireless carriers have already implemented WAP gateways. If a standard HTML document is served in response to an HTTP request from a PDA 10, the WAP gateway server implements content translation before the request can be relayed back to the WAP client 10. The WAP gateway 20 also imposes data quantity limits on client responses. The gateway limitation means that for each given transaction, only a limited number of bytes may pass through the gateway. This so-called “gateway limit” defines the actual amount of data which may be returned in response to an HTTP request.
Generally, the WAP gateways have some form of data limitation on the amount of data which is transmitted to the client 10. In some cases, the gateway limitation is at or about 1.5 Kbytes (or 1492 bytes). Hence, this presents an additional problem to content providers to design pages and applications which can provide useful content and information to a WAP client 10.
Generally, data which is sent by web pages contains both data which the user sees and “meta-data” or information about the data in the web page that is used for a number of purposes, that the users generally do not see. For example, meta-data can include a number of meta “tags” identifying to search engines the type of document which is coded in the HTML in order to allow search engines to quickly determine the type of document it is and return information on the document to users. Other types of lengthy meta-data in web pages may include URLs (universal resource locators) which, given the nature of the Internet and the World Wide Web at present, can be very long. For example, many Internet websites today provide e-mail services to clients. A URL for an e-mail can be quite long, since the URL may contain server information as well as user identification information. Such URLs can easily be 200 bytes in length, and may be embedded in a document and hence unseen to a user.
Long URLs can be particularly problematic for portal sites which seek to provide the user with a customized home page tailored to the user's own design. Such sites allow the user to define the user's specific interests and activities such as mail, local information including weather, movie information, directions, etc., or other personalized information that the user wishes to see when they log on to their personal site. In such a case, links to each of the aforementioned types of information must provide, in the link, specific identification information regarding the type of information which the user seeks to retrieve (i.e. “provide weather information for San Francisco, Calif.”). Hence, it is quite conceivable that a user's customized homepage could have any number of long URL links. Translating this page to a wireless portal, given the WAP gateway limitations mentioned above, would quickly occupy the amount of available bandwidth to transmit the document via gateway to user.